return data[0 : len(data)-1]
	}
	return data
}

// ScanLines is a split function for a [Scanner] that returns each line of
// text, stripped of any trailing end-of-line marker. The returned line may
// be empty. The end-of-line marker is one optional carriage return followed
// by one mandatory newline. In regular expression notation, it is `\r?\n`.
// The last non-empty line of input will be returned even if it has no

	//
	// While this format is compatible with most tar readers,
	// the format has several limitations making it unsuitable for some usages.
	// Most notably, it cannot support sparse files, files larger than 8GiB,
	// filenames larger than 256 characters, and non-ASCII filenames.
	//
	// Reference:
	//	http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06
	FormatUSTAR

		fieldBuf := extra.sub(fieldSize)

		switch fieldTag {
		case zip64ExtraID:
			f.zip64 = true

			// update directory values from the zip64 extra block.
			// They should only be consulted if the sizes read earlier
			// are maxed out.
			// See golang.org/issue/13367.
			if needUSize {
				needUSize = false
				if len(fieldBuf) < 8 {
					return ErrFormat
				}
				f.UncompressedSize64 = fieldBuf.uint64()
			}

		actual := LastIndexByte([]byte(test.a), test.b[0])
		if actual != test.i {
			t.Errorf("LastIndexByte(%q,%c) = %v; want %v", test.a, test.b[0], actual, test.i)
		}
	}
}

// test a larger buffer with different sizes and alignments
func TestIndexByteBig(t *testing.T) {
	var n = 1024
	if testing.Short() {
		n = 128
	}
	b := make([]byte, n)
	for i := 0; i < n; i++ {

// goroutine. When a function F calls panic, normal execution of F stops
// immediately. Any functions whose execution was deferred by F are run in
// the usual way, and then F returns to its caller. To the caller G, the
// invocation of F then behaves like a call to panic, terminating G's
// execution and running any deferred functions. This continues until all

	n := len(b) * count

	if len(b) == 0 {
		return []byte{}
	}

	// Past a certain chunk size it is counterproductive to use
	// larger chunks as the source of the write, as when the source
	// is too large we are basically just thrashing the CPU D-cache.
	// So if the result length is larger than an empirically-found
	// limit (8KB), we stop growing the source string once the limit

	if testing.Short() {
		t.Skip("slow test; skipping")
	}
	t.Parallel()
	// Test a zip file with uncompressed size 0xFFFFFFFF.
	// That's the magic marker for a 64-bit file, so even though
	// it fits in a 32-bit field we must use the 64-bit field.
	// Go 1.5 and earlier got this wrong,
	// writing an invalid zip file.
	const size = 1<<32 - 1 - int64(len("END\n")) // before the "END\n" part
	buf := testZip64(t, size)

	// The C string is allocated in the C heap using malloc.
	// It is the caller's responsibility to arrange for it to be
	// freed, such as by calling C.free (be sure to include stdlib.h
	// if C.free is needed).
	func C.CString(string) *C.char

	// Go []byte slice to C array
	// The C array is allocated in the C heap using malloc.
	// It is the caller's responsibility to arrange for it to be

package bytes_test

import (
	. "bytes"
	"fmt"
	"internal/testenv"
	"io"
	"math/rand"
	"strconv"
	"testing"
	"unicode/utf8"
)

const N = 10000       // make this bigger for a larger (and slower) test
var testString string // test data for write tests
var testBytes []byte  // test data; same as testString but as a slice.

type negativeReader struct{}

			b = append(b, byte(c))
		}
	}
	return string(b)
}

type parser struct {
	err error // Last error seen
}

type formatter struct {
	err error // Last error seen
}

// parseString parses bytes as a NUL-terminated C-style string.
// If a NUL byte is not found then the whole slice is returned as a string.
func (*parser) parseString(b []byte) string {
	if i := bytes.IndexByte(b, 0); i >= 0 {